docs: def load(css_url=None, js_url=None, serve_local=False):
          """Load share.js resources.
  
          :param css_url: if set, will be used as css url.
          :param js_url: if set, will be used as js url.
          :param serve_local: if set to True, the local resource will be used.
          """
          if serve_local or current_app.config['SHARE_SERVE_LOCAL']:
              css_url = url_for('share.static', filename='css/share.min.css')
              js_url = url_for('share.static', filename='js/social-share.min.js')
  
          if css_url is None:
              css_url = 'https://cdn.bootcss.com/social-share.js/1.0.16/css/share.min.css'
          if js_url is None:
              js_url = 'https://cdn.bootcss.com/social-share.js/1.0.16/js/social-share.min.js'
          return Markup('''<link rel="stylesheet" href="%s" type="text/css">\n
              <script src="%s"></script>''' % (css_url, js_url))